Conventional ice making systems and methods can expose the structural components and water/ice to the environment which may contain many contaminants.
An example of a conventional an ice making system and method is disclosed in U.S. Pat. No. 2,149,000. U.S. Pat. No. 2,149,000 shows a method of making chip ice by forming an ice stick in an open ended mold immersed in a body of water to be frozen, then warming the mold to free the ice stick therefrom and permitting ice stick to rise by flotation and then successively cutting off chips of ice from the ice stick as the ice stick rises. The entire content of U.S. Pat. No. 2,149,000 is hereby incorporated by reference.
U.S. Pat. No. 2,145,773 describes a water container having a pair of separate wall areas with a refrigerant evaporator associated with each of the areas connected in parallel in a refrigerant circuit. A thermally controlled valve device alternately closes one and then the other evaporator to control the flow of refrigerant therethrough. The entire content of U.S. Pat. No. 2,145,773 is hereby incorporated by reference.
U.S. Pat. No. 2,821,070 relates to a liquid freezing machine comprising a freezing tube means for refrigerating a tube to freeze liquid therein into a frozen core and means for supplying liquid to be frozen to the tube and for discharging the core from the tube and for discharging the core from the tube including a connection to the tube for supplying liquid to be frozen under pressure to move the core along and out of the tube and at the same time to substantially fill the tube with liquid to be frozen. Liquid flows into the tube at a rate at least as great as that at which the core is ejected from the tube so that the liquid pushes the core from the tube.
A control means operates to open a valve means when the core is to be ejected by the liquid and then to close the valve means to substantially stop the flow of the liquid into the tube upon ejection of the core and upon substantially filling the tube with the liquid to be frozen. A core breaking means is disposed to engage by the core is ejected from the tube and operable to crack the core into pieces. The entire content of U.S. Pat. No. 2,821,070 is hereby incorporated by reference.
U.S. Pat. No. 3,068,660 shows an ice making machine comprising a water tube in which ice is formed, a pump means for circulating water through the tube with a rate of flow sufficient to maintain substantially the entire volume of liquid water in the tube in circulation during the ice freezing operation, a means for refrigerating the water in the tube to form a deposit of ice in the tube, a means for sensing when a predetermined deposit of ice has formed in the tube, means actuated by the sensing means for initiating a thawing operation to loosen the deposited ice in the tube sufficiently to permit movement of the ice through the tube and a means responsive to initiation of the thawing operation for increasing the water flow rate to the tube to cause ejection of the ice from the tube. The entire content of U.S. Pat. No. 3,068,660 is hereby incorporated by reference.
U.S. Pat. No. 3,164,968 describes a liquid freezing machine comprising a freezing tube having an outlet and inlet formed at opposite ends thereof, and a means for supplying the tube between the inlet and the end adjacent thereto with liquid to be frozen through the portion of the freezing tube between the inlet and the outlet. A refrigerating means associated with the freezing tube is disposed to freeze the liquid in the tube into a solid plug. A heating means associated with the freezing tube selectively melts the frozen liquid adjacent the inside of the tube so that the pressure of circulating liquid forces the solid plug of frozen liquid out of the freezing tube. The entire content of U.S. Pat. No. 3,164,968 is hereby incorporated by reference.
U.S. Pat. No. 3,247,677 shows an ice machine having a tubular member with means for pumping water through the tubular member, a means for circulating a refrigerant in contact with an ice making zone of the tubular member, a cooling means for reducing the temperature of the refrigerant below the freezing point of water whereby circulation of the cooled refrigerant in contact with the tubular member will form ice within the ice making zone of the tubular member and a means to bypass the cooling means to subject the tubular member to refrigerant at a temperature in excess of the freezing point of water to free the ice formed within the ice making zone of the tubular member. The entire content of U.S. Pat. No. 3,247,677 is hereby incorporated by reference.
U.S. Pat. No. 3,392,540 relates to a machine for making ice pellets by circulating water to a refrigerant-jacketed inner tube of an evaporator. A pressure sensitive switch stops the flow of refrigerant to the jacket and substitutes hot gas for thawing when the ice formed in the tube is to be harvested. The entire content of U.S. Pat. No. 3,392,540 is hereby incorporated by reference.
U.S. Pat. No. 3,877,242 describes a harvest control unit for an ice-making machine comprising an activatable switch to provide an output signal for electrically initiating a harvest of ice from the machine. The entire content of U.S. Pat. No. 3,877,242 is hereby incorporated by reference.
U.S. Pat. No. 4,104,889 shows an apparatus for transferring ice cubes from a first location to a remote second location including a conduit system between the two locations and a source of air for causing ice to be moved through the conduit system between the two locations. The apparatus further includes diverter means whereby ice cubes being transmitted from the first location to the second location may be diverted to a third location. The entire content of U.S. Pat. No. 4,104,889 is hereby incorporated by reference.
U.S. Pat. No. 6,540,067 relates to an ice transport assembly to transport ice including a sleeve and a tapered auger. Ice at the inlet is transported through a frusto-conically shaped channel and out of an outlet by rotating the tapered auger. The entire content of U.S. Pat. No. 6,540,067 is hereby incorporated by reference.
U.S. Pat. No. 4,378,680 teaches a shell and tube ice-maker with a hot gas defrost having a bottom compartment in which trapped refrigerant gas is present to prevent entry of liquid refrigerant into the compartment during ice-making and from which, during defrosting, hot gaseous refrigerant flows upwardly into the liquid refrigerant which remains in flooded condition around the tubes, whereby delay in initiating further ice-making is minimized. The entire content of U.S. Pat. No. 4,378,680 is hereby incorporated by reference.
U.S. Pat. No. 7,032,406 relates to an ice machine comprising a condensate collection unit disposed beneath an evaporator to collect condensate therefrom and a sump to remove condensate from the ice machine without making contact with recirculated water. The entire content of U.S. Pat. No. 7,032,406 is hereby incorporated by reference.
U.S. Pat. No. 2,387,899 shows an ice-making machine to freeze flowing water within an elongated ice-forming tube into an elongated ice stick or rod and then defrosting the elongated ice-forming tube to release the elongated ice stick or rod therefrom. Once released, the ice stick or rod is broken up into small pieces or fragments for use in icing water coolers or other such structures. The entire content of U.S. Pat. No. 2,387,899 is hereby incorporated by reference.
In the various conventional systems for making and dispensing ice, the conventional ice maker receives water from a water system (that typically has minimum water quality standards) and makes ice while exposing the water, the forming ice, and the ice to ambient air. By allowing the pre-frozen water and the ice to be exposed to the ambient environment, airborne pathogens may come in contact with the water/ice, thereby potentially contaminating the product with harmful pathogens.
For example, the average 1 cubic meter of air contains 35,000,000 particles. In the conventional systems, there is a potential sanitation problem with the exposure of the ice to airborne pathogens. Also, the conventional systems need continual sanitation of the equipment to prevent microbial growth due to airborne mold and bacteria contaminating the moist surfaces of the conventional ice machines.
This exposure to airborne pathogens can lead to visible contamination, unpleasant odors, reliability issues, health inspector issues, and contaminated ice.
In many conventional ice machines, the conventional ice machines draw air for the cooling cycle from the floor drain below the ice machine. By drawing air from below the ice machine, near the floor drain, the conventional ice machines are drawing from a high probable contaminated source, thereby illuminating the need to reduce/eliminate the exposure of the ice making process to the ambient conditions, especially when the ambient conditions have a high probability of having harmful pathogens therein.
In addition, ice machines, conventionally, have relied upon manual sanitizing, automatic sanitizing, ozone, chlorine dioxide, and/or ultraviolet light to reduce/prevent microbial growth.
With respect to manual cleaning, it is conventionally recommended by manufacturers to be done every six months. This process is time-consuming, may require hazardous chemicals, bin cleaning is difficult and disruptive and leads to possible ice waste, and is susceptible to timing and quality issues with respect to when or how well the manual process is performed.
With respect to automatic sanitizing, this process conventionally only sanitizes water contact areas, does not clean the bin or dispenser, and/or may lead to a false sense of security, making the operator incorrectly believe that the ice machine is being fully sanitized.
With respect to ozone, this process conventionally is highly effective, but the process can be toxic if overdone or ineffective if done too little. The ozone process also does provide a reliable measurement of the quality of the sanitizing process, reacts with rubber parts, and/or does not clean the bin. Lastly, ozone generators can be expensive and require periodic maintenance.
With respect to chlorine dioxide, this process conventionally is highly effective, but is costly and potentially hazardous.
With respect to ultraviolet light, this process conventionally can be highly effective, but significant safety and maintenance issues.
In summary, the various conventional systems have drawbacks, can rely on hazardous material, and/or not all clean the ice bin, thereby preventing the production of clean ice.
Conventional systems allow ice machines to get dirty from airborne contamination and then attempt to kill the microorganisms after the microorganisms contaminate the machine.
Conventionally, the microorganisms may be killed after these microorganisms have entered the food zone of the ice machine by actively killing the pathogens using treated surfaces in the food zone, ultraviolet light, or ozone; or by shutting down the machine and killing the pathogens with chemicals which may be poisonous to humans.
An example of a treated surface is the addition of an anti-microbial agent, such as Agion™ anti-microbial, to the materials used to construct the food zone of the ice machine.
It is noted that using an anti-microbial surface material is only effective in killing pathogens if the pathogens come into direct contact with the anti-microbial surface material. This is also true with the use of ozone or ultraviolet light.
However, in the conventional ice machine environment, using this method of killing pathogens is not effective because the ice in the storage bin is mostly in contact with itself, not with the anti-microbial surface area material of the ice machine. Moreover, if slime covers the anti-microbial surface area material, the anti-microbial surface area material must be washed to regain its killing effectiveness.
In contrast, high efficiency particulate filtered positive air pressure keeps an ice machine and bin from being contaminated with air-borne microorganisms. In other words, high efficiency particulate filtered positive air pressure prevents air-borne microorganisms from entering the ice making environment, thereby substantially eliminating the need to clean the ice making system.
Therefore, it is desirable to provide an ice machine that keeps the water, the forming ice, and the ice stored in the ice bin clean.
Moreover, it is desirable to provide an ice machine that makes and stores ice in a cleanroom environment, by preventing contamination and biological growth, keeping the ice and equipment clean at all times, avoiding the use of hazardous materials, and virtually (effectively) eliminating the need to sanitize.
Furthermore, it is desirable to provide an ice machine that substantially eliminates the exposure of the ice making and storing process from ambient contaminants and/or other harmful biological growth, keeping the ice and equipment clean at all times, avoiding the use of hazardous materials, and virtually (effectively) eliminating the need to sanitize.
In addition, in the conventional ice machine environment, there are two zones: the food zone and the mechanical zone, in which there are numerous holes that need to be plugged between the food zone and the mechanical zone, thereby resulting in many holes not being properly sealed during the manufacture process.
If the mechanical zone has a condenser with a fan, the fan will blow or draw air through the condenser to dissipate the heat created when making the ice. In other words, when the condenser fan is turned ON, the condenser fan can blow or draw air through the food zone if the food zone is not sealed properly.
Therefore, it is desirable to provide an ice machine that includes a sealed unitary condenser unit that has a condenser, fan, and fan motor, thereby effectively reducing the air which may be blown into or drawn from the food zone.
As noted above, in the conventional ice machine environment, when the condenser fan is turned ON, it creates either positive or negative air pressure in the mechanical zone which in turn pushes or pulls ambient air through the food zone.
However, the condenser fan is only turned ON intermittently. Thus, when the condenser fan is OFF, and ice is dropped out from an ice automatic ice dispenser, the ice is replaced by air, which is usually sourced from outside the food zone.
In a solution proposed above, high efficiency particulate filtered positive air pressure is realized to prevent air-borne microorganisms from entering the ice making environment.
However, when high efficiency particulate filtered positive air pressure is provided in the ice machine, it has the adverse effect of melting some of the ice.
Therefore, it is desirable to provide an ice machine that includes a high efficiency particulate filtered positive air pressure environment and reduces ice melt.
It is further noted that high efficiency particulate air filtered ice machines need to have field service when installed and continued service thereafter. This service may include commissioning the machine by testing with a certified particle counter and classifying the ice machine with the correct cleanroom classification.
Over time, additional testing is required to verify that the ice machine is maintaining its cleanroom standard, particularly after any filter change.
Also, the ice machine needs to be cultured on a regular basis so that if the ice machine ever becomes biologically unsafe, the ice machine can be sanitized as needed. If the owner of the ice machine does not continue to maintain the cleanroom standard because of not changing the air filter or not culturing on a regular basis, people may become ill from eating the ice from the machine.
Therefore, it is desirable to provide an ice machine that includes a high efficiency particulate filtered positive air pressure environment, wherein the ice machine cannot be operated unless a proper high efficiency particulate air filtering system has been installed.
In addition, it is desirable to provide an ice machine that includes a high efficiency particulate filtered positive air pressure environment, wherein a culture of the ice machine can be realized without substantially interrupting the high efficiency particulate filtered positive air pressure environment.
Lastly, as noted above, in a high efficiency particulate air filtered ice machine, the high efficiency particulate air filters must be changed on a regular basis to maintain clean ice. Also, the actual high efficiency particulate air filter that is used should meet the manufacturer's standards because an inferior high efficiency particulate air filter may fail, causing the production of un-safe ice.
Therefore, it is desirable to provide an ice machine that includes a high efficiency particulate filtered positive air pressure environment, wherein the ice machine can verify that an authorized the high efficiency particulate air filter has been installed.
In addition, it is desirable to provide an ice machine that includes a high efficiency particulate filtered positive air pressure environment, wherein the ice machine can monitor the life of the high efficiency particulate air filter and provide feedback to the owner about replacement and/or shutdown the ice machine when the high efficiency particulate air filter is no longer effective.